Food supply system for a food patty molding machine

ABSTRACT

A patty-forming machine includes a food supply system where the drive mechanism for feed screws use integrated and compact motor and gearbox assemblies. The feed screws have heavy wall thickness flights and the feed screw shafts are journaled through modular bearing assemblies. A conveyor that forms the bottom of the hopper uses a sealed drum motor housed in the drive roller to drive the conveyor. A food supply system includes independent sensing means for indicating whenever the moldable food material accumulated at one end of the hopper exceeds a given level.

This application claims the benefit of U.S. provisional patentapplication Ser. No. 60/881,887 filed on Jan. 23, 2007.

BACKGROUND OF THE INVENTION

Food processors utilize high-speed molding machines, such as FORMAX®MAXUM700®, F-6™, F-12™ F-19™, F-26™, or F400™ reciprocating mold plateforming machine, available from Formax, Inc. of Mokena, Ill., U.S.A.,for supplying patties to the fast food industry. High-speed moldingmachines are also described for example in U.S. Pat. Nos. 3,887,964;4,372,008; 4,356,595; 4,821,376; 4,996,743, and 7,255,554.

The FORMAX® F-26™ reciprocating mold plate forming machine has enjoyedwidespread commercial success for over 35 years. A typical FORMAX® F-26™molding machine can operate at 90 strokes per minute and produce about32,400 patties per hour based on the standard width mold plate for theF-26™ which is about 27 inches wide and can include 6 mold cavities.

The FORMAX® F-26™ molding machine is generally described in U.S. Pat.Nos. 3,887,964; 4,356,595 and 4,996,743. The FORMAX® F-26™ includes asupply system for supplying a moldable food material, such as groundbeef, fish, or the like, to the processing mechanisms of the machine.The supply system comprises a large food material storage hopper thatopens into the intake of a food pump system. The food pump systemincludes at least two food pumps that continuously pump food, underpressure, into a manifold connected to a cyclically operable moldingmechanism.

In the operation of a FORMAX® F-26™ patty-forming machine, a supply ofground meat or other moldable food material is dumped into the hopperfrom overhead. The floor of the hopper comprises a conveyor belt formoving the food material longitudinally of the hopper toward the othercomponents of the food material supply system.

At the forward end of the hopper the food material is fed downwardly bythe supply system into the intake of the reciprocating pumpsconstituting the pumping system. The pumps operate in overlappingalteration to each other; at any given time when the machine is inoperation at least one of the pumps is forcing food material underpressure into the intake of the manifold.

The manifold comprises a valving system for feeding the food material,still under relatively high pressure, into the molding mechanism. Themolding mechanism operates on a cyclic basis, first sliding amulti-cavity mold plate into receiving position over the manifold andthen away from the manifold to a discharge position aligned with aseries of knockout cups. When the mold plate is at its dischargeposition, the knockout cups are driven downwardly, discharging thehamburgers or other molded products from the machine.

The mold plate is connected to a pair of drive arms that extendalongside the housing and are each connected at one end to a swing link.The other end of each link is pivotally connected to one of a pair ofrocker arms which, with a second arm, forms cranks pivoted on a fixedshaft. The free end of each crank arm is connected to a connecting rodassembly that includes a hydraulic shock absorber. The shock absorber isconnected to a mold plate crank arm having a crank pin linked to theoutput shaft of a gear reducer. The gear reducer is driven through avariable speed drive actuated by a mold plate drive motor.

The molding mechanism further comprises a knockout apparatus. Theknockout apparatus comprises the knockout cups, which are affixed to acarrier bar that is removably mounted upon a knockout support member.The knockout cups are coordinated in number and size to the moldcavities in the mold plate; there is one knockout cup aligned with eachmold cavity and the mold cavity size is somewhat greater than the sizeof an individual knockout cup.

A knockout support member is carried by two knockout rods. Each knockoutrod is disposed in an individual housing and is pivotally connected toits own knockout rocker arm.

Each knockout rocker arm is pivotally mounted upon a shaft. Two springsare connected to each knockout rocker arm, biasing the arm towardmovement in a clockwise direction. Clockwise movement of each rocker armis limited by a stop aligned with a bumper mounted in housing.

Each rocker arm is normally restrained against counterclockwise movementby engagement with a knockout cam; the two cams each have a notchaligned with the corresponding notch on the other cam. The cams areaffixed to a knockout cam shaft. The shaft extends across the housing toa right angle drive connection leading to a vertical knockout cam driveshaft that has a driving connection to the mold plate drive gear reduceroutput shaft via a lower right angle drive.

Although the FORMAX® F-26™ patty-forming machine has achieved widespreadacceptance in the industry, the present inventors have recognized theadvantages of an improved patty-forming machine with more flexibility ofoperating control, an increased ease of and reliability of hygienecontrol, an increased smoothness and quietness of operation, andincreased ease of, and reduced cost of, maintenance, an increased speedof operation, and an increased ruggedness of construction.

SUMMARY OF THE INVENTION

The invention provides a patty-forming machine with many improvements tothe food supply system. One improvement is the use of integrated andcompact motor and gearbox assemblies to drive the screw feeders. Furtherthe food supply system comprises the use of modular bearing assembly onthe shafts of the feed screws. The modular attachment of the bearing tothe support plate allows the screw drive assemblies to be removedwithout removing the corresponding bearing assemblies. Also, the feedscrews have heavy wall thickness flights of at least 0.24 inches.

Another improvement is the use of a sealed drum motor housed in thedrive roller to drive the conveyor. In addition, the food supply systemincludes independent sensing means for indicating whenever the moldablefood material accumulated at said one end of the hopper exceeds a givenlevel.

The apparatus of the invention eliminates all sprockets, chains, splineshafts, universal joints, timing belts and pulleys of the currentFORMAX® F-26™ patty-forming machine. The apparatus of the presentinvention is anticipated to achieve a speed of at least 100 strokes perminute.

The apparatus of the invention provides many other improvements thatimprove or enhance the hygiene, maintenance, manufacturing cost,operability of the FORMAX® F-26™ patty-forming machine.

Numerous other advantages and features of the present invention will bebecome readily apparent from the following detailed description of theinvention and the embodiments thereof, and from the accompanyingdrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a right side elevation view of a high speed food patty moldingmachine constructed in accordance with a preferred embodiment of thepresent invention, with some panels and components shown transparent toillustrate underlying components;

FIG. 2 is a partial plan view taken approximately along line 2-2 of FIG.1;

FIG. 3 is an outlet end view taken as indicated by line 3-3 in FIG. 1;

FIG. 4A is an enlarged sectional view of the pumping apparatus for thefood patty molding machine, taken approximately along line 4-4 of FIG.3;

FIG. 4B is an enlarged sectional view of the molding apparatus for thefood patty molding machine, taken approximately along line 4-4 of FIG.3, and is a continuation of FIG. 4A;

FIG. 4C is an enlarged, fragmentary sectional view taken from FIG. 4A;

FIG. 4D is an enlarged, fragmentary end view taken as indicated by line4D-4D in FIG. 1

FIG. 4E is an enlarged, fragmentary top view taken as indicated by line4E-4E in FIG. 4A.

FIG. 4F is an enlarged, fragmentary right end view taken as indicated byline 4F-4F in FIG. 1.

FIG. 5 is a sectional plan view of the pumping apparatus takenapproximately as indicated by line 5-5 of FIG. 1;

FIG. 5A is a sectional view taken generally along line 5A-5A of FIG. 5;

FIG. 6 is a simplified, fragmentary elevation view illustrating thedrive for the molding mechanism of the patty molding machine, with somepanels and components shown transparent to illustrate underlyingcomponents;

FIG. 7 is a fragmentary sectional view of the knockout drive and a partof the mounting apparatus for the molding mechanism of the patty moldingmachine;

FIG. 8 is a diagrammatic view, partly in cross section, of a part of themolding mechanism in a position utilized during change of a mold plate;

FIG. 9 is a fragmentary plan view, partly in cross section, of themolding mechanism;

FIG. 9A is a fragmentary plan view of the knockout apparatus of theinvention;

FIG. 9B is a perspective view of the knockout apparatus of theinvention;

FIG. 10 is a sectional view, taken approximately along line 10-10 inFIG. 9, illustrating the supply apparatus for supplying moldable foodmaterial to the pumps of the patty molding machine, with some panels andcomponents shown transparent to illustrate underlying components;

FIG. 10A is an enlarged, fragmentary sectional view taken generallyalong line 10A-10A of FIG. 10;

FIG. 11 is an enlarged fragmentary sectional view taken generally alongline 11-11 in FIG. 10, with some panels and components shown transparentto illustrate underlying components;

FIG. 12 is an enlarged fragmentary sectional view taken from FIG. 10;

FIG. 13 is a schematic diagram of the hydraulic actuating systememployed in operation of the patty molding machine;

FIG. 13A is a signal schematic diagram corresponding to FIG. 13;

FIG. 13B is a signal schematic diagram corresponding to FIG. 13;

FIG. 13C is a diagram of plunger position versus time;

FIG. 13D is a cross-sectional view of hydraulic line and a hydraulictank employed in operation of the patty molding machine;

FIG. 14 is a simplified diagrammatic perspective view of a mold platedrive system according to the invention;

FIG. 14A is a diagram in elevation view of a portion of the mold platedrive shown in FIG. 14;

FIG. 14B is a diagram in elevation view of a portion of the mold platedrive shown in FIG. 14;

FIG. 15 is an enlarged, fragmentary, left side elevation view of aportion of the apparatus shown in FIG. 14;

FIG. 16 is a fragmentary perspective view of a portion of the apparatusshown in FIG. 14;

FIG. 17 is a fragmentary perspective view of a portion of the apparatusshown in FIG. 14;

FIG. 18 is a fragmentary perspective view of the portion of theapparatus shown in FIG. 17 in a further stage of assembly;

FIG. 19 is a enlarged sectional view taken generally along line 19-19 ofFIG. 4B;

FIG. 20 is a right side elevation view of an access door of the base ofthe patty-forming machine of the present invention;

FIG. 21 is a fragmentary sectional view taken generally along lines21-21 of FIG. 20;

FIG. 21A is a sectional view of a door frame seal element shown in FIG.21;

FIG. 21B is a sectional view of a door seal element shown in FIG. 21;

FIG. 22 is a fragmentary sectional view taken generally along line 22-22of FIG. 20;

FIG. 23 is a fragmentary perspective view at a front portion of thepatty molding machine of the invention with the mold cover lifted in amaintenance position, with mold plate removed;

FIG. 24 is an enlarged fragmentary sectional view taken generally alongline 24-24 of FIG. 23;

FIG. 25 is a fragmentary front perspective view of a portion of thepatty-forming machine;

FIG. 26 is a fragmentary left side perspective view of a portion of thepatty-forming machine;

FIG. 27 is a fragmentary left side perspective view of the portion shownin FIG. 26 and a further stage of assembly;

FIG. 28 is a fragmentary left side perspective view of the portion shownin FIG. 27 in a further stage of assembly;

FIG. 29 is a fragmentary right side perspective view of a portion of thepatty-forming machine;

FIG. 30 is a fragmentary right side perspective view of a portion of thepatty-forming machine;

FIG. 31 is a fragmentary right side perspective view of thepatty-forming machine;

FIG. 32 is an enlarged, fragmentary, diagrammatic right side elevationview of a portion of the machine shown in FIG. 1;

FIG. 33 is a diagrammatic sectional view taken generally along line33-33 of FIG. 32; and

FIG. 34 is a plan view of a floor panel removed from the patty-formingmachine.

DESCRIPTION OF THE PREFERRED EMBODIMENT

While this invention is susceptible of embodiment in many differentforms, there are shown in the drawings, and will be described herein indetail, specific embodiments thereof with the understanding that thepresent disclosure is to be considered as an exemplification of theprinciples of the invention and is not intended to limit the inventionto the specific embodiments illustrated.

The directions “left” side and “right” side of the patty-forming machineare according to the convention shown in FIG. 3.

The General Organization and Operation of the Patty Molding Machine

The high speed food patty molding machine 20 illustrated in FIGS. 1-34comprises a preferred embodiment of the invention. The machine 20constitutes an improvement over the commercially successful FORMAX® F26™patty-forming machine. The FORMAX® F26™ patty-forming machine isgenerally described in U.S. Pat. Nos. 3,887,964 (RE 30,096), 4,356,595and 4,996,743. These patents are herein incorporated by reference toassist in the understanding of the basic operation and configuration ofthe machine 20, except as modified herein.

As shown in FIG. 1, molding machine 20 includes a machine base 21,preferably mounted upon a plurality of rollers or wheels 22. Machinebase 21 comprises an external skin 21 a and an internal frame 21 b andsupports the operating mechanism for machine 20. The base 21 comprises amechanical compartment that contains hydraulic actuating systems,electrical actuating systems, and most of the machine controls.

Molding machine 20 includes a supply system 24 for supplying a moldablefood material, such as ground beef, fish, or the like, to the processingmechanisms of the machine. As generally illustrated in FIGS. 1 and 3,supply system 24 comprises a large food material storage hopper 25 thatopens into the intake of a food pump system 26 (FIG. 5). The exteriorsurface of the storage hopper has a hygienic logo 25 a permanentlyetched into stainless steel surface. The food pump system 26 includes atleast two food pumps, described in detail hereinafter, that continuouslypump food, under pressure, into a manifold 27 connected to a cyclicallyoperable molding mechanism 28. Molding mechanism 28 is provided with anelevator system for use in changing the molding mechanism from oneproduct to another, as described in detail hereinafter.

In the operation of machine 20, a supply of ground meat or othermoldable food material is dumped into hopper 25 from overhead. The floorof hopper 25 comprises a conveyor belt 31 for moving the food materiallongitudinally of the hopper toward the other components of the foodmaterial supply system 24.

At the forward end of hopper 25, the right hand end of the hopper asseen in FIG. 1, the food material is fed downwardly by the supply system24 into the intake of the reciprocating pumps constituting pumpingsystem 26. The pumps of system 26 operate in overlapping alteration toeach other; at any given time when machine 20 is in operation at leastone of the pumps is forcing food material under pressure into the intakeof manifold 27.

The manifold 27 comprises a valving system for feeding the foodmaterial, still under relatively high pressure, into the moldingmechanism 28. Molding mechanism 28 operates on a cyclic basis, firstsliding a multi-cavity mold plate 32 into receiving position overmanifold 27 and then away from the manifold to a discharge positionaligned with a series of knockout cups 33. When mold plate 32 is at itsdischarge position, knockout cups 33 are driven downwardly, dischargingthe hamburgers or other molded products from machine 20, as indicated byarrow A in FIG. 1.

An elevated mirror 25 g allows operating personnel to view inside thehopper 25.

Improved Infeed Conveyor

The food supply system 24 and associated hopper 25 are illustrated inFIGS. 1 and 2. As understood, conveyor belt 31 extends completely acrossthe bottom of hopper 25, around an end roller 35 and a drive roller 36.

According to the invention, the drive roller 36 comprises a sealed drummotor. The sealed drum motor is located inside the roller. Such drumrollers are available from ITOH DENKI. The use of a drum motoreliminates the need for chains and sprockets such that the roller couldbe driven from the machine motor. Furthermore, the use of a drum motorallows the drive to be more effectively sealed since only an electricalconnection need be connected.

Improved Feed Screw System

The forward end of hopper 25 communicates with a vertical pump feedopening 39 that leads downwardly into a pump intake chamber 41. Aninverted U-shaped frame 42 is mounted on machine base 21, extending overhopper 25. The frame 42 comprises a thick support plate 43 affixed toupper portions of a right column 42 a and a left column 42 b. Thesupport plate 43 extends over the pump feed opening 39 in hopper 25.

As shown in FIG. 10, three electric feed screw drives 45, 46 and 47 aremounted upon a motor mount plate 48 that is mounted to and above thesupport plate 43 by long bolts 48 a and end walls 49 a, 49 b. The plate43 includes tapped holes to engage the bolts 48 a. Bolts 50 a andsleeves 48 b extend down from the support plate 43 to hold a cover orshield 48 c around and above the feed screws 51-53.

According to the invention the feed screw drives 45, 46, 47 comprisecompact, integrated electric motor/gearbox assemblies such as SUMITOMOmodel #CNVMO5-6100YC-35, 0.5 horsepower.

Drive 45 drives a feed screw 51 that extends downwardly through opening39 in alignment with a pump plunger 88. Drive 46 drives a centrallylocated feed screw 52, whereas drive 47 drives a third feed screw 53,located at the opposite side of hopper 25 from screw 51 and aligned withanother pump plunger 68.

The feed screws 51, 52, 53 include heavy wall thickness flights of about0.25 inches.

The drives 45-47 are substantially identical and the feed screws 51-53are substantially identical.

The apparatus according to the invention includes a modular feed screwbearing assembly for each drive 45-47. A shown in FIG. 12, by way ofexample, the drive 47 is coupled to a feed screw shaft 53 a by acoupling 53 b. The shaft 53 a is journaled for rotation by a bearingassembly 53 c. The bearing assembly 53 c comprises an outer housing 53 bthat includes upper roller bearings 53 e and lower roller bearings 53 fas well as an upper seal 53 g and lower seal 53 h. The bearing assembly53 c is fastened to the support plate 43. Because the bearing assembly53 c is separately mounted to the support plate 43, the drive 47 can beremoved without removing the bearing assembly 53 c.

The apparatus according to the invention comprises a one piece stainlesssteel feed screw drive enclosure 57. The support plate 43 is placedwithin the enclosure 57 as part of the assembly. A cover 57 a isfastened onto the enclosure 57. The cover 57 a is sealed to theenclosure 57 using a double seal as described with regard to the doorseals in FIG. 21.

The apparatus of the invention provides two independent level sensingelements 54, 55 extending downwardly from shafts 54 a, 55 a as shown inFIG. 10. The level sensing elements are pneumatically biased andconfigured as described in U.S. Pat. No. 7,255,554, herein incorporatedby reference. As the moldable food material 38 is moved forwardly in thehopper 25, it may accumulate to a level at which it engages thedepending sensing fingers 54 and 55. When this occurs, shafts 54 a, 55 aare rotated and actuate limit switches, or send signals to the machinecontrol, to interrupt the drive for roller 36 of conveyor 31, or keepthe conveyor running until both level sensing elements 54, 55 sense highfood product levels. In this manner the accumulation of meat or otherfood material at the outlet end 39 of hopper 25 is maintained at a safelevel.

By making the level sensing elements 54, 55 independent, a closercontrol can be achieved when the food material in the hopper is unevenlydistributed.

When machine 20 is in operation, the feed screw drives 45 and 46 areenergized whenever plunger 88 is withdrawn to the position shown in FIG.5, so that feed screws 51 and 52 supply meat from hopper 25 downwardlythrough opening 39 and into one side of the intake 41 of the foodpumping system 26. Similarly, drives 46 and 47 actuate feed screws 52and 53 to feed meat to the other side of intake 41 whenever plunger 68is withdrawn. In each instance, the feed screw drives are controlled toshut off shortly after the plunger is fully retracted, avoidingexcessive agitation of the meat. As the supply of food material in theoutlet 39 of hopper 25 is depleted, conveyor belt 31 continuously movesthe food forwardly in the hopper and into position to be engaged by feedscrews 51-53. If the level of meat at the outlet end 39 of hopper 25becomes excessive, conveyor 31 is stopped, as described above, until thesupply at the hopper outlet is again depleted. The wall of the hopperoutlet 39 immediately below conveyor drive roller 36 comprises a beltwiper blade 57 that continuously engages the surface of belt 31 andprevents leakage of the meat or other food material 38 from the hopperat this point.

The Food Pump System

The food pump system 26 of molding machine 20 is best illustrated inFIGS. 5, 5A, 7 and 13. As shown therein pump system 26 comprises tworeciprocating food pumps 61 and 62 mounted upon the top 63 of machinebase 21. The first food pump 61 includes a hydraulic cylinder 64 havingtwo ports 65 and 66. A piston 67A in cylinder 64 (FIG. 5A) is connectedto an elongated piston rod 67; the outer end of piston rod 67 isconnected to a large plunger 68. Plunger 68 is aligned with a first pumpcavity 69 formed by a pump cavity enclosure 71 that is divided into twochambers by a partial central divider wall 72. The forward wall 74 ofpump cavity 69 has a slot 73 that communicates with the pump manifold 27as described more fully hereinafter.

The second food pump 62 is essentially similar in construction to pump61 and comprises a hydraulic cylinder 84 having ports 85 and 86.Cylinder 84 has an elongated piston rod 87 connected to a massiveplunger 88 that is aligned with a second pump cavity 89 in housing 71.The forward wall 94 of pump cavity 89 includes a slot 93 communicatingwith manifold 27.

According to the apparatus of the invention a first linear displacementsensor 75 is affixed to the hydraulic cylinder 64 that drives the firstpump plunger 68. A second, identical linear displacement sensor 95 isfixed to the hydraulic cylinder 84 that drives the plunger 88.

The linear displacement sensor 75 is shown in FIG. 5A. The sensor 95 isidentical. The sensor includes a magnet 75 d that influences a sensingrod 75 f that penetrates into the cylinder 64, coaxially into the rod 67to generate a position signal of the cylinder rod 67 with respect to thesensing rod 75 f. Such a sensor 75 is available from BALLUF MICROPULSE®Transducer, Rod Series. The sensors are extremely accurate in reportingrod position to the machine controller.

In FIG. 5, the pumping system 26 is illustrated with the first pump 61pumping the moldable food material into manifold 27 and with the secondpump 62 receiving a supply of the moldable food material for asubsequent pumping operation. Pump 61 has just begun its pumping stroke,and has compressed the food product in pump cavity 69, forcing themoldable food material through slot 73 into manifold 27. As operation ofmolding machine 20 continues, pump 61 advances plunger 68 to compensatefor the removal of food material through manifold 27, maintaining arelatively constant pressure on the remaining food in chamber 69.

As plunger 68 advances, the linear displacement sensor 75 senses thatplunger 68 is near the end of its permitted range of travel. When thisoccurs, pump 62 is actuated to advance plunger 88 through pump cavity89, compressing the food material in the second pump cavity inpreparation for feeding the food from that cavity into manifold 27. Whenthe food in the second pump cavity 89 is under adequate pressure, theinput to manifold 27 is modified so that subsequent feeding of foodproduct to the manifold is effected from the second pump cavity 89 withcontinuing advancement of plunger 88 of the second pump 62. After themanifold intake has been changed over, pump 61 is actuated to withdrawplunger 68 from cavity 69.

Thereafter, when plunger 88 nears the end of its pressure stroke intopump cavity 89, the linear displacement sensor 95 signals to the machinecontrol the need to transfer pumping operations to pump 61. Thechangeover process described immediately above is reversed; pump 61begins its compression stroke, manifold 27 is changed over for intakefrom pump 61, and pump 62 subsequently retracts plunger 88 back to thesupply position shown in FIG. 5 to allow a refill of pump cavity 89.This overlapping alternating operation of the two pumps 61 and 62continues as long as molding machine 20 is in operation.

The Pump Feed Manifold and Valve System

The pump feed manifold 27, shown in FIGS. 5 and 7, comprises a manifoldvalve cylinder 101 fitted into an opening 102 in housing 71 immediatelybeyond the pump cavity walls 74 and 94. One end wall of valve cylinder101 includes an externally projecting shaft 103 connected to a drivelink 104, in turn connected to the end of the piston rod 105 of ahydraulic actuator cylinder 106. Actuator 106 has two fluid ports 12 and13. Two sensing switches 114 and 115 are positioned adjacent piston rod105 in position to be engaged by a lug 116 on the piston rod.

Valve cylinder 101 includes two longitudinally displaced intake slots107 and 108 alignable with the outlet slots 73 and 93, respectively, inthe pump cavity walls 74 and 94. However, slots 107 and 108 areangularly displaced from each other to preclude simultaneouscommunication between the manifold and both pump cavities 69 and 89.Cylinder 101 also includes one or more outlet openings 109. The outletopenings 109 can be as described in U.S. Pat. No. 7,255,554, hereinincorporated by reference.

The valve cylinder outlet opening 109 is generally aligned with a slot111 in housing 71 that constitutes a feed passage for molding mechanism28.

FIG. 5 illustrates the operating condition maintained for manifold 27whenever pump 61 is supplying food material under pressure to moldingmechanism 28. Actuator cylinder 106 has advanced piston rod 105 to theouter limit of its travel, angularly orienting the manifold valvecylinder 101 as shown in these figures. With cylinder 101 in thisposition, its intake slot 107 is aligned with the outlet slot 73 frompump cavity 69 so that food material is forced under pressure fromcavity 69 through the interior of valve cylinder 101 and out of thevalve cylinder outlet openings 109 through slot 111 to the moldingmechanism 27. On the other hand, the second intake slot 108 of valvecylinder 101 is displaced from the outlet slot 93 for the second pumpcavity 89. Consequently, the food material forced into the interior ofvalve cylinder 101 from pump cavity 69 cannot flow back into the otherpump cavity 89.

When molding machine 20 changes over between pump 61 and pump 62,manifold 27 is actuated to its alternate operating conditions byactuator 106, which retracts piston rod 105 and rotates valve cylinder101 through a limited angle in a rotary direction.

In an alternate operating condition, intake slot 107 of cylinder 101 isdisplaced from the first pump cavity outlet slot 73 so that foodmaterial can no longer flow into or out of cylinder 101 from pump cavity69. On the other hand, the other intake slot 108 of cylinder 101 is nowaligned with the outlet slot 93 from pump cavity 89, so that foodmaterial is forced under pressure through slots 93 and 108 into theinterior of cylinder 101 and out of the cylinder through openings 109and 111 to the molding mechanism of the machine.

When pumping from cavity 89 of pump 62 is subsequently terminated, andpumping is resumed from cavity 69 of pump 61 as described above,hydraulic actuator 106 again operates to extend piston rod 105. Themovement of rod 105, through link 104, rotates valve cylinder 101counterclockwise. This restores manifold 27 to the appropriate operatingcondition for pumping of food material from cavity 69 to the moldingmechanism of the machine.

The Molding Mechanism

Improved Mold Plate

The apparatus of the invention is particularly adapted to use a balancedmold plate configuration as described in U.S. application Ser. No.60/844,789, filed Sep. 15, 2006.

Improved Mold Plate Drive

The upper surface of the housing 71 that encloses the pump cavities 69and 89 and the manifold 27 comprises a support plate 121 that projectsforwardly of the housing, and that affords a flat, smooth mold platesupport surface. The mold plate support 121 may be fabricated as aseparate plate bolted to or otherwise fixedly mounted upon housing 71.It includes the upper portion of the manifold outlet passage 111.

Mold plate 32 is supported upon plate 121. Mold plate 32 includes aplurality of individual mold cavities 126 extending across the width ofthe mold plate and alignable with the manifold outlet passageway 111, asshown in FIG. 14. A cover plate 122 including a breather plate 122 a isdisposed immediately above mold plate 32, closing off the top of each ofthe mold cavities 126. The breather plate includes apertures in registrywith the mold cavity and an air exhaust channel back to the food productsupply. Breather plates are disclosed in U.S. Pat. No. 7,255,554, hereinincorporated by reference. A housing 123 is mounted upon cover plate122. The spacing between cover plate 122 and support plate 121 ismaintained equal to the thickness of mold plate 32 by support spacersmounted upon support plate 121; breather plate 122 a rests upon spacerswhen the molding mechanism is assembled for operation. Cover plate 122is held in place by four mounting bolts 125.

Mold plate 32 is connected by a drawbar 127 to a pair of plate drivearms 128 that extends alongside housing 71 and are each connected at oneend to a swing link 129. The other end of link 129 is pivotallyconnected to a rocker arm 131. The rocker arms 131 are fixed onto acenter shaft 131 d to oscillate together. The rocker arms 131 areconnected to a motor drive arm 132 via the center shaft 131 d that isconnected to a crank arm 138 that is driven by the output of the reducer142, forming a crank pivoted on a fixed shaft 133. This arrangement isdescribed more completely in U.S. Pat. No. 3,887,964, and well known asthe construction of the current FORMAX® F-26™ patty-forming machine. Thefree end of crank arm 138 is provided with a lost motion connection asdescribed in U.S. Pat. Nos. 3,887,964 or 4,996,743, herein incorporatedby reference.

Additionally, an improved drive linkage and associated hydraulic circuitcan be provided such as disclosed in U.S. Pat. No. 4,996,743, hereinincorporated by reference.

According to one aspect of the invention, shown in FIG. 14A, the centershaft 131 d is reversible in that it has a spare keyway machined in thecenter shaft 131 d for locking in the motor drive arm 132. The arm 132is connected to the center shaft 131 d at an unequal distance betweenthe rocker arms 131. If one keyway 132 a becomes damaged the centershaft can be reversed (the ends switched) to use a non-damaged keyway132 b.

The apparatus according to the invention provides an improved drive andan improved gear reducer 142. The improved reducer 142 can be an APEXseries AD110 with a 20:1 reduction. The drive includes a servomotor 143connected by a coupling 144 to an input shaft of the reducer 142. Theservomotor is C-face mounted to the reducer with a double envelopingworn gear. This is demonstrated in FIG. 14B wherein a worm gear 142 dwithin the reducer 142 is enmesh with a main gear 142 e to the extentthat it includes an arc 142 f of gear teeth, rather than a minimal pointor line contact.

Preferably, the servomotor is a SIEMENS #1FT6084-8WF71-1TAO servomotorwhich produces a torque of 35NM continuous torque and 65 NM peak torque.

The reducer 142 includes a sleeve 142 a that rotates with the outputshaft 133. The output shaft 133 is keyed to the sleeve 142 a. If theshaft 133 becomes damaged, the output shaft 133 can be removed from thesleeve 142 a without disassembly of the internals of the reducer 142.Also, the input shaft for connection to the coupling 144 is above thecenterline of the shaft 133.

The reducer 142 and the servomotor 143 are water cooled for long life.Domestic water supply 143 g enters both the reducer 142 and theservomotor 143 in parallel streams 143 h, 143 j and exit in parallelstreams 143 k, 143 m. Temperature sensors 143 y, 143 x sense the waterexit temperatures and can communicate an overheating condition to themachine control for either a warning signal or a machine shutdown. Thewater from the outlets 143 k, 143 m is disposed to drain.

The apparatus according to the invention includes longer,non-rectangular drawbar bearings 127 a (FIGS. 9 and 23) for reduced wearand reduced maintenance. The drawbar bearings are preferably composed ofAMPCO 21 and are lubricated. Additionally, the drive arms 128 areconnected to the swing links 129 at a position in front of the rockerarms 131 as shown in FIGS. 14 and 15. This allows for a longer drive armbearing 128 f that comprises inner and outer bearings 128 g, 128 h(FIGS. 17-19). The bearings preferably are composed of C95400 aluminumbronze and are lubricated by oil line 128 m. The pivotal link islubricated by two oil lines 129 j, 129 k as shown in FIG. 15.

Improved Knockout Mechanism

The apparatus of the invention eliminates all sprockets, chains, splineshafts, universal joints, timing belts and pulleys of the currentFORMAX® F-26™ patty-forming machine. The apparatus of the invention isanticipated to achieve a smoother, quieter, more energy efficient andmore controllable machine by using a servo drive for the knockout drive.

Molding mechanism 28 further comprises a knockout apparatus shown inFIGS. 2, 3, 7, and 9-9B. The knockout apparatus comprises the knockoutcups 33, which are affixed to a carrier bar 145 that is removablymounted upon a knockout support member 146. Knockout cups 33 arecoordinated in number and size to the mold cavities 126 in mold plate32; there is one knockout cup 33 aligned with each mold cavity 126 andthe mold cavity size is somewhat greater than the size of an individualknockout cup.

Knockout support member 146 is carried by two knockout rods 147. Eachknockout rod 147 is disposed in an individual housing 148 and ispivotally connected to its own knockout rocker arm 149.

Each knockout rocker arm is pivotally mounted upon a shaft 151. There, apair of springs 152 is connected to each knockout rocker arm 149,biasing the arm toward movement in a clockwise direction as seen in FIG.7. Clockwise movement of each rocker arm 149 is limited by a stop 153aligned with a bumper 154 mounted in housing 123.

Each rocker arm 149 is normally restrained against counterclockwisemovement by engagement with a knockout cam 155; the two cams 155 eachhave a notch 156 aligned with the corresponding notch on the other cam.Cams 155 are affixed to a knockout cam shaft 157.

The apparatus according to the invention comprises a servomotor drive158 to drive the knockout apparatus. The knockout cam shaft 157 isconnected via a coupling 158 a to a gear reducer 158 b that is connectedto a servomotor 158 c. A position target 158 e is provided mounted to adisk 158 f, fixed to the shaft, to register an initial or home positionto a sensor 158 g connected to machine control C.

The servomotor 158 c drives the shaft 157 which drives the knockoutapparatus. Preferably the servomotor is an ALPHA #TPM025-21R-600P-OHproducing a torque of 1500 lb-in nominal torque and 2660 lb-in peaktorque, or a SIEMENS #1FK7042-5AF71-1TAO producing 2.6NM continuoustorque and 10.5 NM peak torque.

The apparatus also includes oil reservoirs 158 j, 158 k that aresubstantially sealed, including a closed top cover, except for windowsin the top cover where wicks 158 m extend from the reservoir to contactwith parts that need lubrication.

As shown in FIGS. 7, 8, 23 and 24, two cover lift rods 161 and 162 areaffixed to cover plate 122 on opposite sides of the machine and extenddownwardly into machine base 21. The lower end of each lift rod 162 issupported by a right angle gear elevator 162 a that is driven by an axle162 b that is driven by a hydraulic motor 162 c via couplings 162 e, 162f as shown in FIGS. 7 and 8. The operation of the lift rod arrangementis well known in the current FORMAX® F-26™ patty-forming machine and isonly described schematically.

During a molding operation, the molding mechanism 128 is assembled asshown in FIG. 7, with cover plate 122 tightly clamped onto spacers. Gearreducer 142 (FIG. 13) is continuously driven by the servomotor 143.

In each cycle of operation, knockout cups 33 are first withdrawn upward,cams 155 pivoting knockout rocker arms 149 to their elevated positionsto lift the knockout cups. The drive linkage from gear reducer 142 tomold plate 32 then slides the mold plate from the full extended positionto the mold filling position, with the mold cavities 126 aligned withpassageway 111.

The lost motion connections in the drive linkage assure some dwell timeat the discharge or knockout position of mold plate 32, so that theknockout cups 33 have time to enter and leave the mold cavities 126while mold plate 32 is at rest. Some dwell at the cavity fillingposition may also be provided. These knockout and fill dwells can alsobe accomplished by programming of the motion profiles of the servomotors143, 158 c such as described in U.S. Pat. No. 7,255,554, hereinincorporated by reference.

Hydraulic cushion 137 allows crank 131 to pick up the mold plate loadover several degrees of rotation, gradually overcoming the mold plateinertia. The lost motion connections and the hydraulic cushion 137incorporated in the drive linkage for the mold plate thus reduce wearand tear on both the mold plate and its drive, assuring long life andminimum maintenance. It may be possible however that with the use of theservomotor mold plate drive, no lost motion or hydraulic cushion will beneeded in the crank driven by the reducer 142.

During most of each cycle of operation of mold plate 32, the knockoutmechanism remains in the elevated position, with knockout cups 33 clearof mold plate 32. When mold plate 32 reaches its extended discharge,however, the notches 156 in the cams 155 are brought into alignment withthe knockout rocker arms 149. Synchronism is maintained between cams 155and mold plate 32 by the machine control.

At this point in the molding cycle, the two knockout rocker arms 149 arepulled rapidly downwardly by the springs 152, pivoting the two rockerarms in a clockwise direction. This movement of the rocker arms drivesthe knockout rods 147 downwardly, moving the knockout cups 33 throughthe mold cavities 126 to discharge molded food patties, from the moldplate 32. The discharged patties may be picked up by a conveyor 172 ormay be accumulated in a stacker. If desired, the discharged patties maybe interleaved with paper, by an appropriate paper interleaving devicesuch as described in detail in U.S. Pat. No. 7,159,372, hereinincorporated by reference or as heretofore known for the FORMAX® F-26™patty-forming machine. In fact, machine 20 may be used with a widevariety of secondary equipment, including steak folders, bird rollers,and other such equipment.

Hydraulic Actuation System and Overall Sequence of Operation

FIG. 13 illustrate a simplified operating hydraulic schematic of theapparatus of the invention. FIG. 13 affords a schematic illustration ofa preferred form of hydraulic actuator system 180 for the food pumps andthe manifold of patty molding machine 20; system 180 also provides abasis for description of a typical pump-manifold operating sequence. Insystem 180, port 65 of cylinder 64 in the first food pump 61 isconnected to one port 191 of a three-position control valve 181. Port 66of cylinder 64 is connected to a second port 192 of valve 181. A thirdport 193 of valve 181 is connected to a high pressure oil line 182 thatis connected to an accumulator 183 and to a high-pressure hydraulic pump184. Pump 184 draws hydraulic fluid from a tank 185 through anappropriate filter 186. Valve 181 is actuated by solenoids 187 a, 187 b.The remaining port 194 of valve 181 is connected to a drain line 188that is returned to tank 185 through a filter 189.

Port 65 of pump cylinder 64 is also connected to one port 195 of athree-position control valve 201, with port 66 of cylinder 64 connectedto a second port 196 of valve 201. Valve 201 is a three-position controlvalve actuated by two solenoids 202 and 203. It includes a third port197 connected to a hydraulic line 199 that is fed from the outlet of alow pressure hydraulic pump 204 having an intake connected to tank 185through a filter 205. The pumps 184 and 204 are driven by a singleelectric motor 206. The remaining port 198 of valve 201 is connected toa hydraulic line 207.

Both the hydraulic lines 182, 199 connect to the tank 185 through agrommet 185 a as shown in FIGS. 13D and 31. The grommet 185 a is fittedinto a hole in the plate 185 b. The plate 185 b is attached with fourfasteners 185 d to the tank 185. A gasket 185 c is positioned betweenthe plate 185 b and the tank 185.

Preferably the tank is composed of stainless steel.

The controls for cylinder 84 of the second food material pump 62 areessentially identical to those of cylinder 64. Thus, port 85 of cylinder84 is connected to one port 221 of a three-position control valve 211actuated by solenoids 217 a, 217 b. Port 86 of cylinder 84 is connectedto a second port 222 of valve 211. The third port 223 of valve 211 isconnected to the high pressure hydraulic line 182 and the fourth port224 of control valve 211 is connected to the drain line 188.

Port 85 of the second pump cylinder 84 is connected to the first port225 of a three-position control valve 231. Port 86 of cylinder 84 isconnected to a second port 226 of valve 231. The third port 227 of valve231 is connected to line 207 and the fourth port 228 is connected toline 228 a. Valve 231 is actuated by two solenoids 232 and 233.

Port 112 of the manifold actuator cylinder 106 is connected to one port235 of a three-position control valve 234; port 113 of cylinder 106 isconnected to a second port 236 of the same valve. The third port 237 ofcontrol valve 234 is connected to line 228 a. The fourth port 238 ofvalve 234 is connected to drain line 188. Valve 234 is actuated bysolenoids 239 a, 239 b. A pressure relief valve 240 may be connectedbetween the low pressure hydraulic supply line 199 and the drain line188.

In considering operation of patty molding machine 20, using thehydraulic actuation and control system 180 of FIG. 13, it may be assumedat the start that the two piston rods 67 and 87 are fully retracted withthe plungers 68 and 88 in their respective cleaning positions, and thatcylinder 106 is fully retracted. In these circumstances, motor 206 isenergized; starting both high pressure pump 184 and low pressure pump204. High pressure oil is accumulated in accumulators 183 and 241 and issupplied to port 112 of actuator cylinder 106.

After a limited period of time, sufficient to allow a build-up of anadequate volume of hydraulic fluid under pressure in the accumulator183, the machine operator actuates a suitable electric control (notshown) to energize solenoids 202 and 232. This alters the portingarrangements for both of the valves 201 and 231, so that low pressureoil is supplied from line 199 to port 65 of cylinder 64, advancingpiston rod 67 and plunger 68 a short distance until the lineardisplacement sensor 75 senses a retracted, ready position. At the sametime, oil under low pressure is supplied, through line 207 and controlvalve 231, to port 85 of the second pump cylinder 84, which advancespiston rod 87 and plunger 88 until the linear displacement sensor 95senses a retracted position. The machine control C de-energizessolenoids 202 and 232, allowing control valves 201 and 231 to return totheir initial operating conditions and interrupting the supply of fluidto the pump cylinder ports 65 and 85. The plungers 68 and 88 are stoppedside-by-side in their respective ready positions, corresponding to theposition of plunger 88 in FIG. 5, with the leading edge of each plungerjust inside pump housing 71.

The machine operator next starts the sequential operation of machine 20by actuating an appropriate electrical control to energize solenoid 202,again supplying low pressure fluid from line 199, through ports 197 and195 of control valve 201, to port 65 of cylinder 64 in the first foodpump 61. As a consequence, piston rod 67 and plunger 68 are advanced,pushing food material into the first pump cavity 69. After a shortperiod of time, plunger 68 stalls against the food material trapped incavity 69.

The linear position sensor 75 detects the presence of resistance infront of a plunger. The position of the resistance is not known. Theplunger advances under constant force. The position of the plunger isconstantly monitored and fed into a moving average filter of fixed time.The average of the positions in the filter will approach the actualposition when resistance to movement is met, in other words, the plungeris slowing down. The control system will stop when the differencebetween the average position and the actual position is within a targetrange. The target range is adjustable as demonstrated by FIG. 13C.

When the presence of pressurized meat is sensed by the sensor 75 as setforth above, solenoid 187 is energized and solenoid 202 is de-energized.Control valve 201 returns to its original operating condition, cuttingoff the low-pressure fluid supply to port 65 of cylinder 64. However,control valve 181 is to connect the high pressure hydraulic fluid line182 to port 65 of cylinder 64. Solenoid 239 of control valve 234 isenergized. This reverses the inlet and drain connections for actuatorcylinder 106, connecting port 113 to the high pressure line 182 andconnecting port 112 to the drain line 188. Actuator cylinder 106 rapidlyadvances piston rod 105, conditioning manifold 27 to feed food materialfrom the first pump cavity 69 to the molding mechanism 28. Plunger 68,under compression, forces food material through the aligned ports ofmanifold 27 and fills the manifold outlet passageway 111 with foodmaterial under relatively high pressure.

At the beginning of the fill portion of the mold plate cycle, controlvalve 181 is actuated to bring its left hand section into alignment withthe hydraulic lines 191-194. This effectively connects pump 184 tocylinder 64 to apply the full pump pressure to port 65 of the cylinder,with port 66 connected to the system reservoir at atmospheric pressure.This causes cylinder 64 and piston 60 to actuate the food pump plunger68 at the maximum fill pressure.

When the fill dwell interval ends and the mold plate begins to movetoward its discharge position, valve 181 is actuated to shift the righthand portion of the valve into alignment with the hydraulic lines191-194. This action connects the output of pump 184 to both of theports 65 and 66 and establishes the conditions necessary for anintermediate pressure condition. This condition is maintained during thetransition interval in which the mold cavities remain in communicationwith the fill passage. Upon completion of that time interval, valve 181is returned to its normal position, blocking access of pump 184 tocylinder 64. This provides the “relieved” pressure condition desired forthe balance of the mold plate cycle. The operation of valve 211 incontrolling the application of the high pressure output from pump 184 tothe second food pump cylinder 84 is the same.

Each time mold plate 32 comes into alignment with the manifold outletpassageway 111, filling mold cavities 126, as described in detail above,plunger 68 jogs forward by a short distance, pushing additional foodmaterial forwardly in cavity 69, into manifold 27, and into the cavitiesof the mold plate. In this manner, plunger 68 of food pump 61 jogs or“jumps” forwardly into cavity 69 each time the mold cavities are filledanew.

As plunger 68 moves into cavity 69, after several cycles of the moldingmechanism, the linear displacement sensor 75 senses that plunger 68 isnear the end of its stroke and that only a minimal amount of foodmaterial remains in cavity 69. The machine control energizes solenoid232 to shift control valve 231 and apply low pressure fluid from line199, through line 207, to port 85 in the second pump cylinder 84. As aconsequence, plunger 88 is advanced, pushing food material into thesecond pump cavity 89. After a short time, plunger 88 stalls against thefood material trapped in cavity 89.

The linear position sensor 95 detects the presence of resistance infront of a plunger. The position of the resistance is not known. Theplunger advances under constant force. The position of the plunger isconstantly monitored and fed into a moving average filter of fixed time.The average of the positions in the filter will approach the actualposition when resistance to movement is met, in other words, the plungeris slowing down. The control system will stop when the differencebetween the average position and the actual position is within a targetrange. The target range is adjustable as demonstrated by FIG. 13C.

When the presence of pressurized meat is sensed by the sensor 95 as setforth above, solenoid 217 is energized to actuate control valve 211 andsolenoid 232 is de-energized, permitting control valve 231 to return toits original operating condition. Under these circumstances, port 85 ofpump cylinder 84 is connected to the high pressure line 182 and port 86is connected to the drain line 188. Accordingly, the food material incavity 89 is placed under high pressure.

At this point, the sensors 75, 95 signal to the machine control foractuation of manifold 27 to its alternate operating condition to feedmolding mechanism 28 from the second pump cavity 89. Solenoid 239 isde-energized, allowing valve 234 to return to its original operatingcondition, with oil supplied under pressure to port 112 of actuatorcylinder 106 and with port 113 connected to drain line 188.Consequently, piston rod 106 is rapidly retracted and the manifold valvecylinder 101 is rotated to the alternate manifold operating condition.Food material can now be pushed into the mold plate cavities by plunger88 moving into cavity 89.

When the changeover of manifold 27 has been completed, by rotation ofvalve cylinder 101, the outlet slot 73 from pump cavity 69 is blocked.Accordingly, plunger 68 can now be retracted to obtain a new supply ofmaterial. The completion of changeover operation in the position of themanifold valve cylinder is signaled by tripping of limit switch 115;actuation of switch 115 de-energizes solenoid 187 and permits controlvalve 181 to return to its original position. This disconnects the highpressure supply line 182 from port 65 of cylinder 64 in the first foodpump 61. Solenoid 203 is energized, shifting control valve 201 to itsthird operating position and connecting the low pressure supply line 199to port 66 of cylinder 64 while port 65 is connected to drain line 188through line 207. This retracts the piston in cylinder 64 and henceretracts piston rod 67 and plunger 68 from the pump cavity 69.Retraction of plunger 68 continues until the linear displacement sensor75 plunger 68 has reached its ready position, just within housing 71,allowing an additional supply of food material to be fed into pump 61 byfeed screw 52 and 53, which are actuated while plunger 68 retracts.

Plunger 68 remains in its ready position until plunger 88 advances byjogging or jumping to a point near the end of its travel into pumpcavity 89. When plunger 88 has moved far enough for linear displacementsensor 95 to sense a nearly depleted meat position, solenoid 202 isenergized. With solenoid 202 energized, control valve 201 is positionedto supply oil from the low pressure line 199 to port 65 of pump cylinder64, advancing plunger 68 to push a fresh supply of food material intopump cavity 69. Plunger 68 stalls against the material trapped in cavity69, and solenoid 202 is de-energized to cut off the low pressure oilsupply to cylinder 64. Signals from the two sensors 75, 95 to themachine control C causes solenoid 239 to again be energized to reversethe valve connections for cylinder 106, supplying high pressure oil toport 113 and connecting port 112 to drain line 188. Accordingly, pistonrod 105 is again advanced and rotates valve cylinder 101 to changemanifold 27 back. Accordingly, food material can now again be forcedinto the mold plate cavities, through manifold 27, by pump 61.

The changeover in manifold 27 to pump 61 again blocks the slot 93 frompump cavity 89, so that the second food pump 62 can be re-charged withfood material. The changeover of the pump manifold trips sensing switch114, which actuates an appropriate electrical control circuit tode-energize solenoid 217, allowing control valve 211 to return to itsoriginal operating condition and cutting off the high pressure oilsupply to pump cylinder 84. Solenoid 233 is again energized, and controlvalve 231 is actuated to its third operating condition. Under thesecircumstances, low pressure oil is supplied through lines 199 and 207 toport 86 of cylinder 84 while port 85 is connected to drain line 188.Accordingly, plunger 88 is retracted to its ready position, solenoid 233is de-energized and valve 231 returns to its original position, themovement of plunger 88 being halted with the plunger in its readyposition as shown in FIG. 5 so that a new supply of food material can befed directly into pump cavity 89 by feed screws 51 and 52 (see FIG. 5).

Plunger 88 waits in its ready position until plunger 68 jogs or jumpsahead to the point near the end of its travel. Solenoid 232 is energizedto begin a slow advance of plunger 88, thus initiating the nextchangeover to the second food pump 62. Operation continues in thismanner, with pumps 61 and 62 working in overlapping alternation, as longas an output is desired from molding machine 20 and a continuing supplyof food material is maintained in hopper 25.

Because the linear displacement sensors 75, 95 are so accurate, oneaspect of the invention provides a control of the hydraulic pressure inthe cylinders 64, 84 based on volume of the mold cavities and the volumeof the plunger “jog.” When the plunger 68, 88 moves forward during afill cycle, the linear displacement sensor very precisely monitors themovement of the plunger. Given the known cross-sectional area of thepump chambers 69, 89, a volume of food product displaced is determinableby the machine control C. The volume of the patty cavities is also knownprecisely. Given that some food product is substantially incompressible,such as ground beef, if the volume of the patty cavities is greater thanthe volume of the plunger displacement within the pump chambers 69, 89then some volume of the patty cavities remains empty.

According to the invention, the machine control could calculate thisshortfall and increase the hydraulic cylinder pressure to ensure that asubstantially equal amount of food product is pumped from the pumpchamber into the patty cavities.

As another aspect of the invention, shown in FIG. 9, mold plates 32 foruse in the patty-forming apparatus 20 are tagged with a radio frequencyidentification (RFID) chip 32 d or other integrated circuit, barcode orother machine readable information source. The chip 32 d would provideinformation which would be read by a sensor 32 h within the apparatus20. Depending on the application, the chip would inform machine controlC the volume of the patty cavities 126 within the mold plate 32 andperhaps initial hydraulic pressure, or recommended hydraulic pressureprofiles over the mold cycle depending on the food product being molded.Also the chip could inform machine control C of any recommended moldplate or knockout movement profiles depending on the product beingmolded.

Improved Hygiene Features

The apparatus of the present invention provides many improved hygienicfeatures; particularly improved seals between mechanical compartmentsand food or spray wash exposed areas.

As illustrated in FIGS. 20-21 the base 21 of the apparatus includesdouble sealed enclosure doors. A door 350 incorporates two rugged hinges351, 352 that are fastened to the edge 354 of the door panel 355. Eachhinge 351, 352 includes a downwardly directed pin 356 that fits into acylindrical socket 360 formed in a hinge post 362, 364 secured to thebase 21; such as to the skin 21 a or to the frame 21 b or to anothersturdy part of the apparatus. Furthermore, the door panel 355 isfastened to the base 21 around a perimeter of the door panel 355 byfasteners 366. A raised flange 370 that defines the door opening holds afirst continuous seal 368 all-around the flange 370. A second continuousseal 374 having an extending lip 375 (FIG. 21B) is fit within an insidechannel 376 provided around the door edge 354. The extending lip 375flexes when compressed against the skin 21 a to form an effective, leakresistant seal. The seals 368, 374 are preferably composed of 40-50 DUROWhite FDA approved NEOPRENE.

The double seal arrangement is used on all of the cabinet doorsincluding the feed screw drives top lid.

According to another aspect of the invention, as illustrated in FIGS. 23and 24, the lift rods 161, 162 are cylindrical in cross-section and aresealed to the base 21 using an annular seal member 380 that comprises afirst member 381 above the base and a second member 382 below the basefastened to the first member 381 through the skin 21 a. At least one ofthe member 381, 382 includes an internal o-ring seal 386. The use of acommercially available cylindrical seal, using a circular o-ring, ratherthan the heretofore known rectangular cross-section seal, makes for amore cost effective and performance effective seal.

The o-ring is preferably composed of BUNA or VITON.

Another improvement in the hygienic configuration of the patty-formingmachine 20 is the fact that the heretofore known trip rods that wereattached to the plungers 68, 88 have been replaced by the lineardisplacement sensors 75, 95 described above. The linear displacementsensors 75, 95 do not extend outside of the base 21 or penetrate theskin 21 a.

As shown in FIGS. 32 and 33, removable stainless steel floor panels orskins 560, 562 are guided like drawers on ledges 566 mounted to thebottom of the machine frame 21 b. The skins 560, 562 are slid inward tooperating position from the left and right sides of the apparatus andthen fastened to a lower frame member. Once unfastened, the skins can bepulled out using handles 565. When the skins 560, 562 are pulled out,the base 21 interior is bottomless and can be spray cleaned more easily.The skins 560, 562 can also be spray cleaned more easily once removed.The skins 560, 562 have outside flanges 560 a, 562 a for fastening tothe frame 21 b and to mount the handles 565, and a surrounding flange560 b, 562 b either upwardly or downwardly directed for rigidity.

As illustrated in FIG. 30, a rectangular plastic seal 390 is now used toseal the mold cover wiring tube 391 which must move vertically when themold cover is lifted. The seal 390 can also include an internal o-ringlike the seal member 380.

As illustrated in FIG. 29 the rectangular control rod 105 of the tubevalve control hydraulic cylinder 106 passes through the sidewall 400. Areplace-able rectangular plastic seal 394 is slid over the control rod105 and fastened against the sidewall 400 using fasteners 395. The seal394 can also include an internal o-ring like the seal member 380 ifnecessary.

As illustrated in FIGS. 25-30, the side compartments 398 which exposethe swing links 129, and the tube valve control cylinder 106 (on theright side) when opened, have been redesigned. The side compartmentsinclude white plastic sidewalls 400. The sidewalls can be composed ofwhite DELRIN. A stainless steel cover plate 402 has a peripheral groove404 that holds a surrounding o-ring 406. The o-ring is preferablycomposed of BUNA or VITON. The cover plate 402 is fastened to thesidewalls 400, to an edge of a top wall 407 and to lugs 408 of the base21.

Air Cooling System

As a further improvement, as shown in FIG. 4A and FIG. 4C, the base 21includes cooling fans 410, 412 that draw outside air through an openingbetween an inlet damper 413 and a top 415 of the surrounding skin 21 a,and through a filter 414 and into the base 21. The cooling fans aremounted to a baffle plate 423. In one embodiment, as shown in FIG. 4Aand FIG. 4D, the cooling fans 410, 412 are located within the base 21below the conveyor belt 13 and between the hydraulic cylinders 64, 84.

The inlet damper 413 is shown in FIG. 4A and FIG. 4D with a dashed linewhen in a held open condition 413 b and in a solid line when in a closedcondition 413. The inlet damper 413 is held open and away from a top ofthe skin 415 by pneumatic actuators 418, 420, 422. The skin 415 containsthe hydraulic cylinders 64, 84. The pneumatic actuators 418, 420, 422are mounted to the baffle plate 423. An outlet damper 430 is provided inthe front of the machine base 21 also held open by pneumatic actuators.The outlet damper 430 is shown in FIG. 1 in an elevated and opencondition 430 by a solid line, and lowered and closed condition 430 b bya dashed line. The inlet and outlet dampers 413, 430 are configured tospring fail closed if power is turned off or lost to the apparatus 20.

The damper 413 has double seals similar to the door 350. An outercontinuous seal element 432 is substantially rectangular incross-section and seals against the skin 415. It is held in an insidechannel 433 fashioned on the damper 413. An inner continuous sealelement 436 is mounted on a surrounding flange that defines arectangular opening 440. The seal element 436 seals against an undersideof the inlet damper 413. The sealing of the outlet damper 430 may bearranged similarly or may be a single element seal or pad

The actuators and the operation of the dampers 413, 430 are as describedin U.S. Pat. No. 7,255,554, herein incorporated by reference. Thepneumatic actuators 418, 420, 422 include extendable rods 424 that arefastened attached to the damper 413. The actuators 418, 420, 422 areconfigured such that when energized with pressurized air the actuatorscylinders extend rods 424 to elevate the damper 413 to the position openposition, held above the inner and outer continuous seals 436, 432.Outside air can be admitted under the cover and up and over the flange440 flange that defines a rectangular opening 440 to the inlet of thefans 410,412 as indicated by the arrows “A.” The actuators 418, 420, 422overcome the compression force of springs 425 within the actuators 418,420, 422 to elevate the damper 413. If the actuators 418, 420, 422 arede-energized, such as by loss of electrical power to the apparatus 20,an electrical switch cuts pneumatic pressure to the actuators 418, 420,422 and the springs 425 urge the damper 413 downward onto the seals 436,432 to close the inlet.

Air passes through the machine and exits the machine base 21 at a frontof the machine base 21. As shown in FIG. 4F, an outlet damper 430 isprovided having a shut off plate 450. The shut off plate 450 ispositioned over an air opening 451 in the base 21. The plate 450 iscarried by a rod 452 via self aligning couplings 453 and are raised andlowered by an actuator 454. The actuator is supported by a bracket 455from the machine base 21 or other stationary structure.

Within actuator 454 are springs (not shown) that are configured to urgethe plates 450 downward from the elevated, open position indicated as430 to the lowered, closed position indicated as 430 b. Duringoperation, actuator 454 is energized and pneumatic pressure elevates theplate 450 to the open position 430, overcoming the urging of the springswithin the actuator 454.

During machine operation, the actuators 418, 420, 422 are energized, andthe dampers 413, 430 are elevated. The fans 412, 410 force air throughthe machine base 21. If power is interrupted to the apparatus 20, anelectrical switch cuts pneumatic pressure to the actuator 454 and theplate 450 is lowered by the springs within the actuator 454 to close theair outlet damper 340.

When the apparatus 20 is washed and sanitized, power is normally shutoff. Because power is interrupted, the inlet damper 413 is automaticallyclosed and the air outlet damper 430 is automatically closed. Thus, thebase 21 is closed-up and spray water and debris is prevented fromentering through the openings closed by the dampers 413, 430.

In one embodiment, as shown in FIG. 4A and FIG. 4D, the cooling fans410, 412 are located within the base 21 below the conveyor bet 13 andbetween the hydraulic cylinders 64, 84. The first fan is positioned inlongitudinal line with the second fan in relation to said base. Thesecond cooling fan 412 is disposed ahead of first cooling fan 410 withinthe base 21. The cooling fans 410, 412 are disposed in series in a linethat coincides with the conveying direction of the conveyor belt 13.

Improved Electrical Features

Electrical equipment is mounted on a swing-out chassis 650 as shown inFIG. 31. The chassis 650 is hinged by a hinge axle 652 and hinges 653 atone side. The chassis 650 includes door hinge posts 362 on an oppositeside to the hinge axle 652, and lugs 664 for attachment of the chassis650 to the base 21. The door 350 described above connects to the hingeposts 362 by the hinges 351, 352 and fastens to the base 21 around theflange 370.

A 15 inch touchscreen monitor 670 is provided for operator interface tothe machine 20. The monitor is 180 degree rotatable about a post 672.The post 672 is inverted L-shaped and is fixed to an underside of thesupport plate 43 (FIG. 10).

Modular distributed intelligent I/O distribution blocks are used whereinthe signal cables 680 from the solenoids 187 a, 187 b, 201, 202, 232,233, 217 a, 217 b, 239 a, 239 b are connected to a serial block 682 anda single serial cable 686 is then routed to machine control. Thisconfiguration reduces manufacturing costs and cable clutter inside themachine. The system is described in FIGS. 13 and 13B.

While the particular preferred and alternative embodiments to thepresent invention have been disclosed, it will be appreciated that manyvarious modification and extensions of the above described technologymay be implemented using the teaching of this invention.

1. A food supply system comprising: a hopper; a conveyor configured tosupply food material to a feed system; said conveyor forming the bottomof said hopper; the feed system includes a pump feed opening, a firstindependent sensing element and a second independent sensing element;the hopper communicates with a pump feed opening for providing a pathtoward a molding mechanism; the first independent sensing element isconfigured to indicate the level of moldable food material in a firstarea of the feed system; and the second independent sensing element isconfigured to indicate level of moldable food material in a second areaof the feed system.
 2. A food supply system comprising: a hopper; aconveyor configured to supply food material to a feed system; saidconveyor forming the bottom of said hopper; said feed system for movingfood material toward a molding mechanism; said feed system comprising afeed screw drive and a modular feed screw bearing assembly forsurrounding a feed screw shaft at an intersection with a firsthorizontal support plate; said feed screw bearing assembly and said feedscrew drive are each independently attached to said first support plate;and said feed screw drive independently removable from said supportplate; the feed screw bearing assembly is vertically orientated andmounted on the first support plate and extends from the first supportplate toward a lower horizontal second support plate, the first supportplate is spaced apart from the second support plate.
 3. The food supplysystem according to claim 2, wherein said feed system comprises a feedscrew connected to said feed screw drive; said feed screw has wallflights having a thickness of at least 0.24 inches.
 4. The food supplysystem according to claim 2, wherein said feed screw drive is mounted toa third horizontal support plate located above feed screw bearingassembly and above the first support plate; the third support plate isconnected to the first support plate with a space between said third andfirst support plates.
 5. The food supply system according to claim 2,comprising a feed screw with a feed screw shaft; the feed screw shaft isjournaled through the bearing assembly and coupled to an output shaft ofthe feed screw drive.
 6. The food supply system according to claim 5,wherein the feed screw, feed screw drive, and feed screw bearingassembly are vertically aligned.
 7. The food supply system according toclaim 2, wherein the second support plate comprises a recess and aportion of the bearing assembly opposite the first support plate engagesthe recess.
 8. The food supply system according to claim 1, comprising amachine controller signal connected to the feed screw drive and thefirst and second sensing elements, the controller having instructionsfor sending a stop signal to the conveyor when each sensing elementsindicate food material is at a predefined level.
 9. The food supplysystem according to claim 1, comprising a machine controller signalconnected to the conveyor and the first and second sensing elements, thecontroller having instructions for sending a signal to the conveyor tocause the conveyor to operate when either the first or the secondsensing element indicates food material is below a predefined level. 10.The food supply system according to claim 1, comprising a machinecontroller signal connected to the conveyor and the first and secondsensing elements, the controller is configured to correct an unevenlydistributed food material load at the feed screw as based on the signalsfrom the first or the second sensing elements by operating the conveyoruntil both sensing elements indicate food material is at a predefinedlevel.
 11. The food supply system according to claim 1, wherein the feedsystem comprises a feed screw located above the pump feed opening andadjacent to the first and second sensing elements; the feed screw drivenby a feed screw drive axially aligned with the feed screw.
 12. The foodsupply system according to claim 1, wherein the feed system comprises atleast three feed screws; the sensing elements are located between thefeed screws.
 13. The food supply system according to claim 12, whereinthe feed screws are located above the pump feed opening; the feed screwsare driven by corresponding feed screw drives axially aligned with thecorresponding feed screw.
 14. The food supply system according to claim12, wherein the sensing elements extend vertically in the spaces betweenthe feed screws.
 15. The food supply system according to claim 2,comprising a plurality of feed screws, and said feed screw bearingassembly comprises a corresponding plurality of modular feed screwbearing assemblies, and said feed screw drive comprises a correspondingplurality of feed screw drives; each feed screw is journaled through oneof said bearing assemblies and connected to one of said feed screwdrives to form a feed screw drive group; each feed screw is axiallyaligned with the corresponding bearing assembly and the correspondingfeed screw drive; the feed screw drive groups are laterally aligned. 16.The food supply system according to claim 1, wherein each of the firstand second sensing elements each comprise a sensing rod attached to apivot shaft, wherein the position of the pivot shaft about its axis ofrotation indicates the position of the sensing rod and correspondingly alevel of food material within the feed system.
 17. Food patty formingapparatus comprising: a hopper; a food supply mechanism in the hopperconfigured to supply food material from the hopper to a feed system; thefeed system includes a pump feed opening, a first independent sensingelement and a second independent sensing element; the hopper incommunication with a pump feed opening to provide a path toward amolding mechanism; the first independent sensing element is configuredto indicate the level of moldable food material in a first area of thefeed system; and the second independent sensing element is configured toindicate level of moldable food material in a second area of the feedsystem.
 18. The food patty forming apparatus of claim 17, comprising amachine controller signal connected to the food supply mechanism and thefirst and second sensing elements, the controller configured to stop tothe conveyor when each sensing elements indicate food material hasexceed a predefined level.
 19. The food patty forming apparatus of claim17, comprising a machine controller signal connected to the food supplymechanism and the first and second sensing elements, the controllerconfigured to signal the operation of the conveyor when either the firstor the second sensing element indicates food material is below apredefined level.
 20. The food patty forming apparatus of claim 17,comprising a machine controller signal connected to the food supplymechanism and the first and second sensing elements, the controllerconfigured maintain an even distribution of food material in the firstand second areas of the feed system by operating the conveyor until boththe first and second sensing elements indicate food material is at leastat a predefined level.